Rockwell Automation 150 MNL/SMC DIALOG+/APP-PROD GUIDE - Manual (Page 152)

Chapter
7
Design Philosophy
Philosophy Allen-Bradley’s SMC controllers are designed to operate in today’
industrial environments. These controllers are manufactured to
provide consistent and reliable operation.
Line Voltage Conditions Voltage transients, disturbances, harmonics and noise exist in any
industrial supply. A solid-state controller must be able to withstand
these noises and should not be an unnecessary source of generating
noise back into the line.
• Ease of selection for the required line voltage is achieved with a
design that provides operation over a wide voltage range, at 50/60
Hz, within a given controller rating.
• The controller can withstand 3000V surges at a rate of 100 bursts
per second for 10 seconds (IEEE Std. 472). Further, the
controller can withstand the showering arc test of 350–1500V
(NEMA Std. ICS2-230) for higher resistance to malfunction in a
noisy environment.
• An optional MOV module is available to protect SCRs from
voltage transients.
Current and Thermal Ratings Solid-state controller ratings must ensure reliability under the wid
range of current levels and starting times needed in various
applications.
• SCR packaging keeps junction temperatures below 1 2 ° C
(25 ° F) when running at full-rated current to reduce thermal
stress and provide longer, more reliable operation.
• The thermal capacity of the SMC Dialog Plus controllers meet
NEMA standards MG-1 and IEC34 (S1).
Mechanical Shock and
Vibration Solid-state controllers must withstand the shock and vibration
generated by the machinery that they control.
• SMC Dialog Plus controllers meet the same shock and vibration
specifications as electromechanical starters. They can withstand
a 30G shock for 11 ms in any plane and one hour of vibration of
2.5G without malfunction.